This part of ISO 10307 specifies two procedures — A (thermal) and B (chemical) — for the accelerated ageing of residual fuel oils. When combined with the hot filtration method specified in ISO 10307-1, these procedures permit the prediction of fuel oil stability, as affected by sedimentation, during storage and handling of the fuel oils. NOTE For the purposes of this International Standard, the terms “ ” and “ ” are used to represent mass and volume fractions of a material, respectively. These expressions are deprecated under the International System and according to ISO 31-0, Quantities and units — Part 0: General principles, which specifies that mass and volume fractions be expressed as “mass fraction of xx %” (symbol ) and “volume fraction of xx %” (symbol ).